Ultrahigh energy storage in process-engineered NaNbO₃-based thin films with superior thermal and cyclic stability

Abstract Dielectric thin film capacitors are essential for miniaturized electronics and energy storage systems, offering ultrafast charge-discharge rates and high reliability. However, achieving high energy density, efficiency, and stability in lead-free systems remains challenging, particularly wit...

Full description

Saved in:
Bibliographic Details
Main Authors: Alexander M. Kobald, Herbert Kobald, Theresa Gindel, Ivana Panzic, Marco Deluca
Format: Article
Language:English
Published: Nature Portfolio 2025-07-01
Series:Scientific Reports
Subjects:
Online Access:https://doi.org/10.1038/s41598-025-05243-2
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract Dielectric thin film capacitors are essential for miniaturized electronics and energy storage systems, offering ultrafast charge-discharge rates and high reliability. However, achieving high energy density, efficiency, and stability in lead-free systems remains challenging, particularly with scalable and cost-effective methods. Here, we demonstrate relaxor sodium niobate-based thin films with Bi and Mg substitution, synthesized via optimized chemical solution deposition. By tailoring crystallization temperature and heating rate, we achieved a recoverable energy density of 37 J cm−3 and an efficiency of 80% at 2.45 MV cm−1. The films exhibit exceptional thermal stability, with energy density variation below 10% up to 310 °C, and superior charge-discharge stability beyond 16 million cycles at high fields. Microstructural engineering, involving grain size reduction and enhanced granularity, was critical for achieving a high Weibull breakdown strength (2.29 MV cm−1) and reliability. These films outperform previously reported sodium niobate systems, surpassing lead-based alternatives in environmental sustainability and scalability. Our approach highlights the potential of sodium niobate-based thin films for high-performance dielectric capacitors in harsh environments, offering a scalable pathway for environmentally sustainable energy storage technologies.
ISSN:2045-2322